This invention deals generally with vapor chambers and more specifically with a structure for a vapor chamber which is easily adaptable to high volume production.
Vapor chambers are often used in cooling electronic circuitry, but they are typically limited in operating temperature by the boiling point of the working fluid. If the boiling point of the working fluid is exceeded, the vapor pressure will be beyond atmospheric pressure thus creating positive pressure on the inside of the vapor chamber. If this happens, the planarity of the vapor chamber envelope can be compromised and in extreme cases will cause the envelope to rupture releasing the working fluid and destroying the device and possibly the adjacent electronics. A common means of overcoming this limitation is by bonding a pillar-like support structure between the upper planar plate lid of the vapor chamber and the bottom base plate, typically by soldering or brazing. This technique can overcome the temperature limitation of the vapor chamber; however it may not be practical, especially in high volume production. Consistency between braze joints can be difficult to achieve, because it is very dependent on the temperature uniformity of the parts undergoing the brazing process. This is especially true when an internal wick structure is in close proximity to the braze joint, and acts as wick for the liquid braze. This ultimately damages the wick structure and also compromises the braze joint.
It would be very beneficial to have a system for assembling the vapor chamber that maintained the planar structure of the upper lid and the base plate by preventing their distortion, but was also simple to assemble and did not interfere with the action of the wick.